Bulldozer blades for moving earth, snow and the like are well known. Usually they are supportably mounted on a vehicle through a push frame, including a pair of substantially parallel push arms which are pivotally elevated with retraction of a lift jack connected between the forward portion of the vehicle and the back of the blade. Over the years, the support system and blade construction has become more complex in order to better resist heavy loads and to allow the blade to be adjusted to various working attitudes. Exemplifying such bulldozer blade arrangements are U.S. Pat. Nos. 2,311,553 to R. G. LeTourneau; 2,963,802 to J. M. Gwinn, Jr.; 3,503,457 to J. R. Smith et al. In addition, U.S. Pat. Nos. 3,025,620 to R. K. Liess and 3,395,764 to L. A. Wirt, and assigned to the assignee of the present invention, are particularly representative of bulldozer blade arrangements which are used for more severe working applications such as prying out boulders, tree trunks and the like under heavy impact loads.
As is also known, the bulldozer blades of the above mentioned type incorporate a forwardly disposed moldboard and a plurality of plates which are weldably secured rearwardly to the moldboard so that a cellular blade frame is provided for maximum strength with less weight. Typically, a plurality of support brackets are weldably secured to the rear face of such blade frame after it is completely fabricated, with the result that these brackets and their peripheral weld joints suffer various forms of failure after severe use. Moreover, even though some blades have utilized support brackets which have been limitedly built into such a blade frame, they have not been satisfactory because of their fabricated piece-part construction or their poor load transmitting relationship with respect to other plate members intermediate the bracket itself and the moldboard.